In conventional telephone systems, incoming calls cause a ringing sound to alert the recipient. Typically, a mechanical switch called a “hook” relays the incoming call's ring signal to a bell or loudspeaker to sound as long as the handset is on the hook, and relays incoming signals to the low volume speaker in the handset for conversation when the handset is lifted off the hook.
Internet telephony stations based on personal computers in many cases use a headset as illustrated in FIG. 1, which positions a small speaker over one ear of a user and positions a microphone in front of the user's mouth. Headsets are used, instead of a computer's loudspeakers, because audio feedback from the loudspeakers into its microphone could interfere with telephone conversations. Since headset speakers are positioned close to the listener's ear, their volumes are low. When the headset is not being worn, and the computer's loudspeakers are not in use, possible rings of incoming calls could go unnoticed.